Role of thymectomy in myasthenia gravis.

Thirteen patients with myasthenia gravis underwent total thymectomy between January, 1988 and December, 1991. The duration of symptoms prior to surgery varied from 2 months to 20 years. In a follow-up ranging from 2 months to 4 years, 11 patients showed a significant improvement with either complete discontinuation of medication or a marked reduction in doses. One patient with a small benign thymoma showed some improvement but subsequently required stepping up of anticholinesterase medication and addition of steroids and immunosuppressants; another patient with atrophic thymic tissue had complete remission after thymectomy but developed myasthenic symptoms six months later requiring medication again. Thymectomy is recommended for all patients with generalised myasthenia gravis with or without thymoma regardless of the duration of disease unless the patient is a very high risk candidate for surgery. It is not recommended for isolated ocular myasthenia gravis.